Facility Constraints Research Articles

An Efficient Optimization Work Flow for Field-Scale In-Situ Upgrading Developments

Summary In-situ upgrading process (IUP) is an attractive technology for developing unconventional extraheavy-oil reserves. Decisions are generally made on field-scale economics evaluated with dedicated commercial tools. However, it is difficult to conduct an automated IUP optimization process because of unavailable interface between the economic evaluator and commercial simulator/optimizer, and because IUP is such a highly complex process that full-field simulations are generally not feasible. In this paper, we developed an efficient optimization work flow by addressing three technical challenges for field-scale IUP developments. The first challenge was deriving an upscaling factor modeled after analytical superposition formulation; proposing an effective method of scaling up simulation results and economic terms generated from a single-pattern IUP reservoir-simulation model to field scale; and validating this approach numerically. The second challenge was proposing a response-surface model (RSM) of field economics to analytically compute key field economical indicators, such as net present value (NPV), by use of only a few single-pattern economic terms together with the upscaling factor, and validating this approach with a commercial tool. The proposed RSM approach is more efficient, accurate, and convenient because it requires only 15–20 simulation cases as training data, compared with thousands of simulation runs required by conventional methods. The third challenge is developing a new optimization method with many attractive features: well-parallelized, highly efficient and robust, and with a much-wider spectrum of applications than gradient-based or derivative-free methods, applicable to problems without any derivative, with derivatives available for some variables, or with derivatives available for all variables. This work flow allows us to perform automated field IUP optimizations by maximizing a full-field economics target while honoring all field-level facility constraints effectively. We have applied the work flow to optimize the IUP development of a carbonate heavy-oil asset. Our results show that the approach is robust and efficient, and leads to development options with a significantly improved field-scale NPV. This work flow can also be applied to other kinds of pattern-based field developments of shale gas and oil, and thermal processes such as steamdrive or steam-assisted gravity drainage.

Reliability Improvement in Beam Pumps by Use of a Unique Methodology

This article, written by JPT Technology Editor Chris Carpenter, contains highlights of paper SPE 171372, “Reliability Improvement in Beam Pumps by Use of a Unique Methodology Combining Real-Time Automation and Failure Analysis,” by Blair Gardner, SPE, Santos, prepared for the 2014 SPE Artificial Lift Conference and Exhibition—North America, Houston, 6–8 October. The paper has not been peer reviewed. This paper focuses on analysis of beam-pump-failure root causes and trends and how the operator has used these data combined with automated equipment to reduce failure frequency and operating cost. The paper also presents data and findings to support the benefits of a beam-pump-automation and -control program. Introduction The operating company has operated a fleet of beam pumps in the Cooper basin in central Australia since 1985. The basin extends over 30 000 km2 in a remote, harsh, arid desert. Ambient air temperature can range from 0°C to greater than 50°C, and there is potential for flood events in the wet season. The remote location and variety of weather conditions present numerous operational challenges and technical constraints. Historically, the beam pumps have run in a traditional manual mode whereby production operators measure, record, and analyze operating parameters and monitor surface-equipment condition. The operator implemented an automation program in 2006 to help improve run life; increase production; and decrease environmental, health, and safety risk. Artificial-Lift Selection The operator installs and operates many mainstream artificial-lift systems (ALSs) including electric submersible pumps (ESPs), progressing-cavity pumps (PCPs), jet pumps, and beam pumps. Artificial lift is installed on every oil well, with selection criteria being based on the expected fluid rate in conjunction with any surface- facility constraints. The operator installed its first beam pump in 1985; these have been the dominant ALS for yielding fluid rates from 20 to 1,000 BFPD, a range into which most oil wells fall. In 2005, a decision was made to switch to PCPs as the preferred ALS for new wells; this decision was reversed back to beam pumps in 2008 following poor PCP reliability. Past Operating Strategy Failure Diagnosis and Analysis. In the past, following discovery of a suspected downhole failure, the operator would run a standard suite of diagnostics, which included collecting a manual dynacard and running a pump-up pressure test, before placing the well “on tap” (or tagging bottom) in an attempt at reinstating production. If this was unsuccessful, the well was transferred to the production engineer to justify and scope a downhole-repair workover. No formal record of diagnosis or activities attempted to reinstate pumping action was preserved. Once a pump repair was executed, the rig reports were filed in the field-office well file. Consequently, information regarding the root cause of failure was often inconsistent in reporting standard, and it was not recorded and collated systematically in any central repository to enable future analysis. Cooper Basin and the Digital Oil Field—Beam-Pump Automation and Telemetry Implementation. In 2006, none of the operator’s Cooper basin beam-pump fleet had any form of automation or telemetry. One of the outcomes of the unsuccessful PCP program was a better understanding of the benefit that control and telemetry have on artificial-lift performance and reliability. When the switch was made back to beam pumps as the preferred ALS, it was evident that some level of automation would be required. The operator retrofitted two platforms of control to its beam-pump fleet. The selection criteria were based predominantly on individual-well economics, rather than a generic approach. Variable-Speed Drive (VSD) (Advanced). A VSD is used to automatically adjust an electric motor and, consequently, pump speed to match well inflow; target pump fill is used as a feedback loop to the VSD control algorithm. Benefits include maximized production by self-optimization, advanced condition monitoring, and equipment protection. This is the preferred system for all new beam-pump installations. Pumpoff Control (POC) (Basic). A rod-pump controller (RPC) was retrofitted to existing engine-driven beam pumps that could not justify the cost of VSD installation. The system has no ability to self-optimize; however, the RPC shuts the pump down if a severely pumped-off condition is reached or if rod-load limits are exceeded. Benefits include basic condition monitoring and equipment protection.

Cardiovascular Disease Risk and Barriers to Physical Activity

BACKGROUND: The prevalence of obesity is increasing and tends to be higher in adult population groups who are also more educated and employed as a civil/military/police/oficers. This study aims to analyze cardiovascular disease (CVD) risk, perceptions about physical activity and barriers experienced to perform physical activity, also stage of change to physical activity.METHODS: The study design was an observational study, use qualitative methods with in-depth interviews and quantitative analysis CVD risk also stage of change to physical activity questionnaire.RESULTS: Framingham 10-years CVD risk of obese men in University of Surabaya was 11.97% (1.70 to 29.90) based on lipid profile and 13.90% (2.30 to 30.00) based on body mass index. Perception of obese men in University of Surabaya regarding physical activity had findings several barriers that can be grouped into time constraint, facility constraint, low motivation, and knowledge about physical activities.CONCLUSION: In this study we found that 10-years CVD risk of obese men in University of Surabaya can be categorized as medium risk. There are several barriers regarding life style modification for physical activity and exercise, whereas the subjects included in this study are quite ready to start the program, but improvement for the readiness before starting the program will still be needed.KEYWORDS: CVD risk, obese men, physical activity

Instrumentation, control and data acquisition system with multiple configurations for test in nuclear environment

The In-Vessel Viewing System is a 3D laser scanning system which will be used to inspect the blanket first wall in ITER. To make the IVVS probe design compatible with the harsh environmental conditions present in ITER, a test campaign was performed in 2012–2013 to verify the adequacy of the main components of the IVVS probe. The IVVS components inspected were an optical encoder, passive components and two customized ultrasonic piezoceramic motors that were instrumented with various sensors. A general architecture of the Data Acquisition and Control System (DACS) was defined and then specialized for each test. To be suitable for this test campaign, the DACS had to host various I/O modules and to properly interface the driver of the customized piezo motors, in order to permit the full control of the test and the acquisition of experimental data. This paper presents the instrumentation solutions designed and implemented for different facilities constraints and the related DACS developed in four specialized versions for the described test campaign.

A Case Study of Integrated Asset Modeling for Gas Fields Sharing Production Facilities

This article, written by Special Publications Editor Adam Wilson, contains highlights of paper SPE 169918, ’A Case Study of Integrated Asset Modeling To Support Reservoir- Management Strategies for Four Dry-Gas Fields Sharing Production Facilities,’ by O. Espinola, SPE, M. Rocha, SPE, and N.C. Alvarez, SPE, Schlumberger, and J.R. Ramirez, A. Solis, and J.D. Guzman-Arevalo, Pemex, prepared for the 2014 Trinidad and Tobago Energy Resources Conference, Port of Spain, Trinidad and Tobago, 9-11 June. The paper has not been peer reviewed. Integrated asset modeling (IAM) properly models the interaction of fields producing through common production facilities and yields reliable production forecasts, compared with the use of independent models. Using integrated asset models helps validate independent models, honor facilities constraints, and, in general, support the decision-making process in reservoir management. This paper describes a case study in which four reservoir models were coupled with a production-network model, with the objectives of maximizing recovery factors, identifying operational problems, and evaluating water-production effects. Introduction Among the recent discoveries made by Pemex Veracruz Asset are four dry-gas fields with different geological and dynamic properties that must be produced through shared production facilities to be economic. This poses a complex operational scenario involving several questions that need to be answered: What is the optimum exploitation rhythm for each reservoir and its interaction on the surface? On the basis of the fact that one reservoir has an aquifer, what will be the effect on the recovery factor, and what are the challenges at the surface level? Regarding the differences in pressures and volumes, the selection of the compression stages will be difficult because each reservoir will require different capacity and startup dates. What, then, is the optimum compression scheme that generates the maximum value from an economic perspective? As part of the field-development plan, the incorporation of new wells or a new field will be evaluated. What will be the effect of these new elements on the system? To face all these challenges, a multidisciplinary team was appointed to analyze the system from different perspectives and design several exploitation strategies and evaluate them both technically and economically to select the optimum one to produce the fields. The strategies should Manage reservoir pressures to reduce backpressure effects. Minimize the risk to produce water and support the design of water-handling facilities. Identify the wells with liquid-loading problems and low potential. Define the startup date of each compression stage so that all reservoirs benefit at the same time. Evaluate the scenarios economically, considering two schemes—buying and renting compression facilities. Evaluate the effect of future developments, such as workover, infill drilling, and the incorporation of a new field.

A Mixed-Integer convex formulation for production optimization of gas-lifted oil fields with routing and pressure constraints

Production optimization of gas-lifted oil fields under facility, routing, and pressure constraints has attracted the attention of researchers and practitioners for its scientific challenges and economic impact. The available methods fall into one of two categories: nonlinear or piecewise-linear approaches. The nonlinear methods optimize simulation models directly or use surrogates obtained by curve fitting. The piecewise-linear methods represent the nonlinear functions using a convex combination of sample points, thereby generating a Mixed-Integer Linear Programming (MILP) problem. The nonlinear methods rely on compact models, but can get stuck in local minima, whereas the piecewise-linear methods can reach globally optimal solutions, but their models tend to get very large. This work combines these methods, whereby piecewise-linear models are used to approximate production functions, which are then composed with convex-quadratic models that approximate pressure drops. The end result is a Mixed-Integer Convex Programming (MICP) problem which is more compact than the MILP model and for which globally optimal solutions can be reached.

Iranian EFL teachers’ perceptions of the difficulties of implementing CALL

AbstractDespite the spread of reliable technological tools and the availability of computers in Iranian universities, as well as the mounting evidence of the effectiveness of blended learning, many Iranian language teachers are still reluctant to incorporate such tools in their English as a foreign language (EFL) classes. This study inspected the status quo of technology integration in Iranian EFL classes and investigated the obstacles, as perceived by the Iranian EFL teachers, toward implementing CALL in Iran. First, 100 EFL teachers completed the Teacher Technology Integration Survey developed by Vannatta and Banister (2009), to help estimate technology use in EFL classes. Then the researchers interviewed twelve teachers, comprising two EFL teacher educators with no CALL experience, four teachers with the experience of integrating technology in their EFL classes, four EFL teachers who had recently finished an online CALL teacher education program, and two EFL teachers with no CALL experience. The semi-structured interview questions were designed by the researchers, one of whom has extensive experience with CALL, and were revised based on the suggestions of a colleague with expertise in teacher education. One of the researchers conducted the interviews, each of which lasted for 30–50 minutes. The researchers used structural content analysis of the interview transcripts to find themes relevant to the research question. The results suggest that on the whole, Iranian EFL teachers do not usually integrate digital technology into their classes; and the obstacles in implementing CALL in language classrooms could be classified into three categories: teacher, facility, and learner constraints. Each of the categories is discussed in detail and suggestions are provided for promoting CALL in the Iranian context.

Efficiency improvement of an antibody production process by increasing the inoculum density

Increasing economic pressure is the main driving force to enhance the efficiency of existing processes. We developed a perfusion strategy for a seed train reactor to generate a higher inoculum density for a subsequent fed batch production culture. A higher inoculum density can reduce culture duration without compromising product titers. Hence, a better capacity utilization can be achieved. The perfusion strategy was planned to be implemented in an existing large scale antibody production process. Therefore, facility and process constraints had to be considered. This article describes the initial development steps. Using a proprietary medium and a Chinese hamster ovary cell line expressing an IgG antibody, four different cell retention devices were compared in regard to retention efficiency and reliability. Two devices were selected for further process refinement, a centrifuge and an inclined gravitational settler. A concentrated feed medium was developed to meet facility constraints regarding maximum accumulated perfundate volume. A 2-day batch phase followed by 5 days of perfusion resulted in cell densities of 1.6 × 10(10) cells L(-1) , a 3.5 fold increase compared to batch cultivations. Two reactor volumes of concentrated feed medium were needed to achieve this goal. Eleven cultivations were carried out in bench and 50 L reactors showing acceptable reproducibility and ease of scale up. In addition, it was shown that at least three perfusion phases can be combined within a repeated perfusion strategy.

Increasing constructive engagement and positive affect for residents with severe and very severe dementia through group‐based activities

A group-based multisensory activity program (Sensory Day) for residents with dementia was developed, to address the challenge of providing personalised activities within tight operational constraints in residential aged care facilities. Fourteen participants with severe and very severe dementia were observed before, during and after participation in one of four Sensory Day sessions. The Menorah Park Rating Scale was used to yield four levels of engagement. The Philadelphia Geriatric Affect Rating Scale was used to identify four affect states. Dementia severity was ascertained by PAS-CIS scores mapped onto the Global Deterioration Scale. Increased levels of constructive engagement and positive affect were observed during participation in the Sensory Day sessions, relative to measures taken before the session. This novel approach to activity programming demonstrates that it is possible to provide group-based activities for residents with severe and very severe dementia which result in increased engagement and positive mood.

A computational analysis of multidimensional piecewise-linear models with applications to oil production optimization

Production optimization of gas-lifted oil wells under facility, routing and pressure constraints is a challenging problem, which has attracted the interest of operations engineers aiming to drive economic gains and scientists for its inherent complexity. The hardness of this problem rests on the non-linear characteristics of the multidimensional well-production and pressure-drop functions, as well as the discrete routing decisions. To this end, this work develops several formulations in Mixed-Integer Linear Programming (MILP) using multidimensional piecewise-linear models to approximate the non-linear functions with domains spliced in hypercubes and simplexes. Computational and simulation analyses were performed considering a synthetic but realistic oil field modeled with a multiphase-flow simulator. The purpose of the analyses was to assess the relative performance of the MILP formulations and their impact on the simulated oil production.

Reservoir management using streamline-based flood efficiency maps and application to rate optimization

Abstract 3-D streamlines provide an effective tool for reservoir management because of their ability to display reservoir flow and well connections in a physically intuitive manner. Streamlines have been extensively used to investigate the interaction between heterogeneity and well patterns and also for rate allocation and pattern balancing. More recently, streamlines have been used in conjunction with constrained optimization techniques for improving waterflood performance via rate control. Field scale rate optimization problems, however, involve highly complex reservoir models, production and facilities constraints and a large number of unknowns, making them inaccessible for routine waterflood management. In this paper we provide a simple and easy to use workflow for waterflood rate optimization using streamline-based flood efficiency maps that display the flux and time of flight distribution amongst producing wells. We demonstrate the use of flood efficiency map to optimize the injection/production rates to maximize waterflood sweep efficiency by equalizing the average time of flight (TOF) amongst the producing wells in regional basis. Our optimization approach is extremely efficient because it relies on simple analytic calculations to compute weighting factors for injection and production rates to minimize the TOF variance amongst producing wells. Because the approach does not rely on formal and complex optimization tools, it is particularly well-suited for large-scale field application. Also, the approach can be used with both streamline and finite difference simulators. For finite-difference simulations, the streamlines and time of flight are derived from the flux field generated by the simulator. Multiple examples are presented to support the robustness and efficiency of the proposed waterflood management scheme. These include 2D synthetic examples for validation and a 3D field application.

Integrated modelling of entire production network and topsides facilities for production optimisation of major oil and gas fields

An oil company sought to identify bottlenecks in three of their main oil and gas production networks. It was desired to, therefore, develop the entire production network from wells, flowlines, intra-field and inter-field pipelines, and export pipelines up to the onshore terminal first stage separator/slug catcher, all in the transient multi-phase-flow oil and gas (OLGA) simulator. Furthermore, the detailed topsides facilities were separately modelled in a process simulator. The OLGA and process simulator models were subsequently integrated, where the flow simulator model received boundary pressures from the topsides model and pushed through the mass flows of the individual phases into the process simulator. After field-matching and tuning the integrated models to the given field data, optimising the overall fields’ production and performance was carried out, powered by a market-leading optimisation engine. The main optimisation parameters were: wellhead choke openings; gas lift rates and allocations; and topsides operating conditions, facility constraints and control tuning parameters. The network models were used to investigate the dynamic behaviour of wells and pipelines as well as surface process facilities equipment and control systems, with the aim to improve productivity of the entire field networks. The development of the integrated and dynamic well, pipeline and process models is part of company initiatives to facilitate the design and operational support tools for the company’s engineers.

의료법상의 원격의료 제도에 관한 고찰

The rapid development of the current information and communication brings big changes and progress in the health service delivery system. And it is becoming the worldwide trend increasingly. As the name of medical information, by more rapid, detail and more quickly to the patients and diagnosis of the disease it provides not only a high level of health care services but also hospitals and related institutions are making increase the efficiency of the work. Among them, the Telemedicine, that system has many advantage which can expect the shorten the waiting time and the uniform high level of medical, etc. without visiting medical institutions. Especially, the most advantage is it can increase the accessibility of information about extensive medical, without regard to the time and place. But this is the reality, which compared speed the development of modern science and technology with lack of operational regulations and mindset. Current in our Medical Law, it regulates the Telemedicine, but it has Institutional, facility, and environmental constraints. Because, there is no detailed legal relationship. And it takes that in terms of a special form called by a non-face-to-face contact with medical practice rather than the scene. Therefore, in this paper will find a way out to activate the Telemedicine by presupposes the development potential is infinite and find the legal issues and improvements.

여가스포츠활동 유형별 여가제약 분석

본 연구는 여가활동 중에 국민들이 선호하는 여가스포츠활동의 참가를 유도하고 지속할 수 있도록 여가스포츠활동 유형을 개인종목, 대인종목, 단체종목으로 분류한 후 각 유형에 따른 여가제약을 규명하고자 하였다. 본 연구는 서울과 경기도에 거주하는 여가스포츠활동 참여자를 대상으로 하였다. 편의표집방법을 활용하여 총 286명이 연구에 참여하였다. 여가스포츠활동 참여자의 여가제약은 시설환경, 부정인식, 여건부족, 부상위험, 시간부족의 5가지 요인으로 분류되었다. 본 연구의 결과는 첫째, 여가제약 요인 중 시설환경요인이 가장 높은 것으로 나타났으며 부정인식요인이 가장 낮은 것으로 나타났다. 둘째, 여가스포츠활동 참가정도에 따른 여가제약의 차이는 부정인식요인, 여건부족요인에서 부분적으로 차이가 나는 것으로 나타났다. 셋째, 여가스포츠활동 유형에 따른 여가제약의 차이는 시설환경요인, 부정인식요인, 여건부족요인, 부상위험요인에서 부분적으로 차이가 나타났다. 이러한 결과를 바탕으로 여가스포츠활동 참가 정도와 유형에 따라 여가제약에 대한 차이가 있다는 것을 규명하였으며 이러한 결과는 맞춤형 여가제약 협상에 대한 연구들도 가능하게 할 것이며 미래 여가사회연구를 위한 중요한 자료가 될 것이다. The purpose of this study was to investigate leisure constraints based on the types of leisure sports activity(individual, partner, and group activities) in order to lead people to participate in and to continue their leisure sports activities. Data were collected from leisure sports participants in Seoul and Kyungki province. A total of 286 respondents were selected using the convenience sampling method. Leisure constraint's sub-dimensions for the respondents were named as facility and environment, negative perception, lack of condition, risk of injury, and lack of time. As the results of this study, first, respondents felt facility and environmental constraint the most and negative perception constraint the lowest. Second, there were differences in negative perception and lack of condition constraints based on the magnitude of participation. Finally, there were differences in facility and environment, negative perception, lack of condition, and risk of injury constraints based on the types of leisure sports activity.

Reproductive performance of rams in three producer range flocks: Evidence of poor sexual behavior in the field

Poor mating behavior increases ram costs and extends the lambing season while decreasing genetic progress. Producers recognize the importance of ram libido; however, time, labor, and facility constraints limit routine evaluation of males for libido. The current experiment determined the incidence of low- and high-sexually performing rams based on the number of lambs sired by each ram in three range flocks. Rams were evaluated for breeding soundness prior to joining with females. Genomic DNA was extracted from blood samples collected from all rams, and approximately one-third of the lambs and their dams. Microsatellite markers were used to determine parentage. Number of lambs expected to be sired by each ram was established by calculating 99% confidence intervals, based on the expectation that each ram would have equal number of lambs. Rams siring more or less lambs than expected were categorized as high or low sexually performing rams, respectively. Paternity was established for >80% of the lambs sampled. Rams which had higher than expected numbers of lambs made up 23–29% of the ram population but sired from 39.4% to 70% of the lamb crop. Low performing rams (23–43% of the ram population) sired from 3.2% to 16.2% of the lamb crop. Since fertility was evaluated prior to mating, differences in ram fecundity may reflect the expression of sexual behavior in a multi-sire range flock setting. Rams are generally selected for breed characteristics and potential influence on flock genetics will be greater for high- than low-sexually performing rams.

The Shanghai–Beijing “Air Express” Service Model and its Impact on the Pricing Behaviour of Airlines

Using departure day airfare data, this paper examines the pricing pattern on the Shanghai–Beijing route and reveals anti-competitive pricing behaviour following the introduction of the “Air Express” service. This new service adds limited value to passengers because of the airport facility constraints. Jointly providing the “express” service has provided a channel through which the three dominant players can communicate effectively to achieve more stable prices at a higher level. Interestingly, lower prices charged by the fringe airlines on this route were accommodated by the big ones. Meanwhile, the three dominant airlines did not exhibit any obvious deviation in pricing from each other.

Erratum to: Factors influencing the uptake of a mechatronics curriculum initiative in five Australian secondary schools

While the ready-made Lego™ Robotics kits are popular in schools and are used by students at both primary and secondary year levels, using the Picaxe microcontroller (chip) to create simple electronic devices, including robotic devices is less popular. The latter imposes an additional challenge as a result of the need to construct the universal board with the chip in it—a challenge embraced in the cross-disciplinary mechatronics program in this study. This paper reports on how teachers from five Australian secondary schools put into practice technological pedagogical content knowledge (TPCK) developed from expert-led workshops and explores factors (intrinsic and extrinsic) that influenced the implementation. The results show that different strategies were adopted by the schools in implementing the programs. While teacher attitude played an important role in influencing the program’s success, being able to identify where the program sits within the curriculum and planning around timetable and facility constraints were also important factors to consider. The research indicated that teachers’ TPCK was most challenged in non-obvious areas such as diagnosing where faulty soldering joints were.

Development Optimization Using Reservoir Response Surfaces: Methods for Integrating Facility and Operational Options

The objective of a field development optimization process, or workflow, is to investigate various options and determine a course of action that will deliver the largest expected value from an asset. The analysis is often complicated by uncertainty in important inputs. Ideally, operators desire workflows and tools that integrate reservoir engineering and optimization principles in a fast-solving model that can be used to explore the full range of the uncertain inputs. This need is acute in the screening and concept selection stage where the primary objective is to determine the sensitivity of competing concepts to the sources of uncertainty. In these early stages, model results can be used to determine whether additional information should be collected, and to narrow down the number of competing options. The objective of this research is the development of a workflow and tool that integrates reservoir response surfaces within a project optimization model that contains facility and operational options, and to use this model to investigate the impacts of uncertainty on decision making. The integration of technical options is critical because a static view of capital investment and facility constraints causes a systematic undervaluation and can introduce error to development decisions. The new workflow and integrated reservoir-economic optimization tool developed in this research leverage methods and engineering work products that are already known to industry, for example, experimental design (ED) and response surface methods (RSMs). A demonstration is provided for a gas flood project using a stylized reservoir. Specifically, we investigate the selection of initial well configurations and injection capacities while simultaneously accounting for the options to update these decisions after production information is acquired in the early periods of production. The workflow is used to optimize the development of a gas flood. As a second step, the workflow is used to solve a value of information problem.

A Descriptive Study on Level II Fieldwork Supervision in Hospital Settings

ABSTRACTThe objective of this study was to examine the factors influencing fieldwork educators’ ability and willingness to supervise Level II occupational therapy students in hospital-based settings. Qualitative focus groups were used to explore the perceptions of occupational therapists in four urban hospitals in Nebraska. The study presents the issues facing fieldwork supervisors and their suggestions on how to improve the fieldwork process. Both personal and professional factors influenced occupational therapists’ willingness to accept students, while facility constraints were the primary reason occupational therapists would not accept Level II students. Fieldwork educators believe that their facilities need structured fieldwork programs and that students need more formalized fieldwork preparation at their academic institutions. Themes highlight the need for continued collaborative endeavors between academic fieldwork coordinators and fieldwork educators.

Bringing the First BP-Operated Subsea-to-Shore Gas Field Into Production: Flow-Assurance Lessons Learned

Summary Taurt field, located in the Mediterranean Sea in 108-m water depth, is the first BP-operated subsea-to-shore gas development. Phase 1 of the project consists of two subsea wells producing directly from the subsea manifold to the onshore gas-processing plant with a 68-km, 20-in. pipeline. The field has been brought into production and was successfully ramped up to 230 MMscf/D despite facility constraints during initial startup. The main flow-assurance issues experienced during the initial startup are hydrate risks because of Joule-Thomson (J-T) cooling and liquid-production handling onshore, particularly because of potential completion-brine return. The experience during initial startup highlights the importance of collecting good fluid samples during exploration and appraisal, and obtaining downhole and wellhead pressures and temperatures during flowback. Confirming the condensate yield helps prediction of liquid holdup in the pipeline that will affect the prediction of liquid production coming onshore during ramp up. More-accurate prediction of the wellhead temperature affects the requirement for hydrate inhibitor, which also affects the liquid holdup in the pipeline and liquid production coming onshore. Transient simulations help in selecting the dewatering strategy to be either a pigged or a pigless operation by predicting the amount of remaining water and how it impacts the production ramp up. Simulations also help prediction of the liquid production for setting up temporary liquid-handling facilities to prevent the possibility of completion-brine return upsetting the processing plant. Comparison with the actual liquid-production data suggests that simulations should have been performed with less-conservative condensate yield, although predicting the completion-brine return onshore is still difficult. After obtaining the latest fluid composition and the actual operating conditions, the hydrate-management strategy was revisited, and this resulted in cost savings and simpler operating procedures.